Preheat oven to 350°F (177°C). Grease three 9-inch round cake pans, line with parchment paper rounds, then grease the parchment paper. Parchment paper helps the cakes seamlessly release from the pans. (If it’s helpful, see this parchment paper rounds for cakes video & post.)

In a large bowl, whisk the flour, baking powder, baking soda, and salt together. Set aside. Using a handheld or stand mixer fitted with a paddle or whisk attachment, beat the butter and sugar together on medium-high speed until smooth and creamy, about 3 minutes. Scrape down the sides and bottom of the bowl with a silicone spatula as needed. On medium-high speed, add 1 egg at a time, beating well after each addition. Beat in the vanilla extract. Scrape down the sides and bottom of the bowl as needed.

With the mixer on low speed, add the dry ingredients in three additions, alternating with the buttermilk, beginning and ending with the dry ingredients, and mixing each addition just until incorporated. Do not over-mix. The batter will be smooth, velvety, and slightly thick.

Pour the batter evenly into the prepared pans and smooth the tops. For even cake layers, use a kitchen scale and weigh the cake pans for accuracy. You should have around 8 cups of batter total (a little over 1800g), so each cake pan should have about 2 and 2/3 cups (a little more than 600g) of batter.

Bake for 25–26 minutes or until the cakes are baked through. To test for doneness, insert a toothpick into the center of the cake. If it comes out clean, it’s done. Allow cakes to cool completely in the pans set on a cooling rack. The cakes must be completely cool before frosting and assembling.

In a large bowl using a handheld mixer or stand mixer fitted with a whisk or paddle attachment, beat the butter on medium speed until creamy—about 2 minutes. Add 5 and 1/2 cups (660g) confectioners’ sugar, 5 Tablespoons (75g) heavy cream, vanilla extract, and salt with the mixer running on low speed. Gradually increase to high speed and beat for 3 full minutes. Add 1/2 cup (60g) more confectioners’ sugar if frosting is too thin, 1 more Tablespoon cream if frosting is too thick, or a pinch more salt if frosting is too sweet. Yields about 4.5 cups (1080g) of frosting.

Watch the video for a tutorial on assembling and decorating this naked cake. First, using a large serrated knife, slice a thin layer off the tops of the cakes to create a flat surface. Discard (or crumble over ice cream!). Place 1 cake layer on your cake stand, cake turntable, or serving plate. Spread 1 and 1/2 cups (360g) of frosting evenly on top. If using, dot half of the raspberries around the rim. Flatten them down into the frosting as best you can so the cake layer on top is sturdy. Top with 2nd cake layer and evenly cover the top with another 1 and 1/2 cups of frosting and more (flattened!) raspberries around the rim. You can sprinkle a few leftover raspberries in the center, too. (Like I did in the video.) Top with the third cake layer. Spread the remaining frosting on top and all around the sides using an icing spatula. Use a bench scraper to smooth out the frosting on the sides of the cake. If you’re making a fully naked cake, spread the remaining frosting on just the top of the cake. If you have leftover frosting, you can freeze it for up to 3 months.

Decorate the cake with garnishes.

Refrigerate the cake for at least 2–3 hours or up to 1 day before slicing and serving. If chilling for more than a few hours, loosely cover with plastic wrap (or the lid of a cake carrier) after 1 hour of refrigeration. (The frosting will “set” after about 1 hour and the plastic wrap won’t really ruin your frosting at that point.) And if you’re chilling for more than a few hours, I suggest decorating with garnishes right before serving, so they look fresh.

Cover and store leftover cake at room temperature for up to 1–2 days or in the refrigerator for up to 1 week.